Intelligence transmission system



Feb. 12, 1957 Filed May 1, 1952 E. E. SUCKLING INTELLIGENCE TRANSMISSIONSYSTEM veer/m:

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[as/ace [f Shaw/1 g BY FM 0/?- WW Feb. 12, 1957 E. E. SUCKLINGINTELLIGENCE TRANSMISSION SYSTEM 3 Sheets-Sheet 3 Filed May 1, 1952INVENTOR Eusfare 1?. Sari/ 55f B Km J? MGM United States PatentINTELLIGENQE TRANSMISSION SYSTEM Eustace E. Suckling, Brooklyn, N. Y.

Application May 1, 1952, Serial No. 285,582

3 Claims. (Cl. 340-318) This invention relates to systems ofintelligence transmission and particularly to systems for the remotereproduction of transmitted intelligence in the form of clearly visibleand easily readable characters on the face of a cathode ray tube.

Systems relating to the remote reproduction of transmitted intell' e inthe form of large visible characters have a espread utility inthesignaling art, and many devices directed towards this end, bothmechanical and electrical, are well known. In general the mechanicaldevices known to the art are characterized by dial pointers, numberwheels and like arrangements and are of limited utility because of theirrelatively slow operating characteristics, extensive space requirements,complication of construction, objectionable "limitations of distanceover which the intelligence may be mechanically transtitted.

The older mechanical systems have, at the present day, been largelydisplaced by electrical systems which in general do not have thedeficiencies, at least to the same extent, that characterize and limitthe utility of the earlier devices. in electrical intelligencetransmission systems the utilization of the cathode ray tube for thereproduction of the transmitted intelligence in the form of visiblecharacters is gaining favor and is making inroads into the fieldsdominated by the earlier electrical systems which usually utilized banksof lights or similar arrangements selectively actuated for character orcoded intelligence reproduction devices.

Intelligence transmission or display systems utilizing a. cathode raytube for the reproduction of transmitted intelligence in the form ofreadable characters thereon all basically require the application ofparticularly shaped voltage waves to the vertical and horizontaldeflection plates thereof in order to control the disposition of thecathode ray beam for the production of letters, symbols or otherintelligence on the lace of the tube. In conventional cathode ray tubesystems the required voltage Waves are usually generated bycarefullycontoured rotatable capacitors in association with complicatedswitching mechanisms to effect the presentation of different characterson the face of the tube, and as such. are relatively expensive and arepractically limited to the successive presentation of individualcharacters onthe full tube face. Oth r aptations of the basic cathoderay tube systems utilize a stepped horizontal positioningvoltage for thepresentation of a plurality of characters on the face of the tube.However, inclusion of facilities for such type of presentation only addsfurther complications to the detrimental complications of the existentswitching mechanisms as mentioned above. Moreover, present dayelectrical systems conventionally require auxiliary equipment ofcomplicated nature to code or otherwise transform the intelligence to betransmitted into suitable electrical impulses preparatory to Wave formgeneration, which wave forms are of such character as to preclude or atleast render impracticable, transmission thereof by conventionaltelephone or telegraphlines.

2,781,508 Patented Feb. 12, 1 957.

In addition to the above, present day device-s are conventionallylimited to the successive presentation of individual or a plurality ofindividual characters at fixed locations on the face of the tube and donot permit the presentation of a continuity of sequentially reproducedintelligence adapted to move across the face of the tube so as topresent a continuity of reproduced intelligence similar to that viewedby the eye when scanning a line of print.

This invention may be briefly described as an improved intelligencetransmission system of simple and inexpensive construction for theremote reproduction of transmitted intelligence in the form of readilyvisible and easily readable characters continuously and sequentiallypresented on the face of a cathode ray tube, including method andapparatus for converting the intelligence desired to be transmitted intosimple wave forms readily transmitta'ble over conventional telephone andtelegraph lines, in conjunction with apparatus and methods for theremote reproduction of the transmitted intelligence on the face of acathode ray tube utilizing an external synchronized horizontal sweepthereof as an integral and essential component of the controlling waveform applied to the horizontal deflection plates.

The primary object of this invention is the provision of an improvedintelligence transmission system for the remote reproduction or.transmitted intelligence.

Another obiect of this invention is the provision of an improvedintelligence transmission system wherein the transmitted intelligencemay be continuously read as the reproduction thereof is continuously andsequentially dis placed across the face of a cathode ray tube.

Another object of this invention is the provision of an intelligencetransmission system whereby the intelligence desired to be transmittedmay be readily converted into form for transmission and is convenientlystorable in said form.

Another object of this invention is the provision of means and methodsfor translating the intelligence desired to be transmitted intoelectrical impulses of simple wave form that may be readily transmittedover conventional telephone and telegraph lines.

Another object of this invention is the provision of methods and meansfor translating the intelligence desired to be transmitted intoconvenient form that permits remote reproduction thereof in continuousform and in motion if desired.

A further object of this invention is the provision of methods andapparatus for the production of particularly shaped and contoured waveforms that are adapted to be combined with the locally generated cathoderay tube horizontal sweep voltage at the receiving station to generate acomposite controlling wave form for intelligence reproduction purposes.

Other objects and advantages of the invention will be pointed out in thefollowing disclosure and claims and illustrated in the accompanyingdrawings which disclose, by Way of example, the principles of theinvention and the presently preferred embodiments of the intelligencetransmission system applying those principles.

Referring to the drawings: I

Fig. 1- schematically illustrates the essentials of a transmitter andreceiver unit constructed in accordance with the principles ofthe'inventiori;

Figs. 2a through 2 d schematically illustrate the wave shape contours ofthe components of the cathode ray tube deflection voltages for theproduction of an example character;

Fig. 3 schematically illustrates an alternative construction foratransmitterunit; and

Fig. 4.is a schematic illustration of the essentials of apparatussuitable fortpreparation of a transmitting tape including a schematiccircuit diagram of a ratio modulation circuit as utilized in the unit.

Referring to Fig. 1, there is illustrated a receiver unit designated Aincluding a conventional cathode ray tube provided with verticaldeflection plates 12 and 12a, horizontal deflection plates 14 and 14aand a beam intensity control grid 16. In the illustrated tube thedeflection plates 12a, 14a are grounded forthe purpose of simplicity ofexplanation. Connected to the vertical deflection plate 12 is anamplifier 18 of conventional construction for suitably amplifying thevertical deflection voltages applied to said plate 12. Similarlyconnected to the ungrounded horizontal deflection plate 14 is a mixingnetwork 20 adapted to receive the output voltage wave form of ahorizontal sweep generator 22 and the transmitted horizontal deflectionvoltage wave form as amplified by a conventional amplifier 24 andprovide a composite horizontal deflection voltage wave form forapplication to said plate 14. In order to control the intensity of thecathode ray trace for blanking purposes intermediate sequentiallypresented characters and where desired in the formation of certaincharacters, the intensity control grid 16 is connected to an amplifier26 adapted to amplify the transmitted blanking signals prior to ap- Ioutput of the sweep generator 22 and the transmitted and contoured waveform as amplified by the amplifier 24. The polarity of the transmittedwave form amplified by the amplifier 24 is such as to oppose theconventional left-to-right displacement of the cathode ray beam producedby the saw-tooth wave generated by the sweep generator 22 and thetransmitted horizontal wave forms are readily produced of such contourand amplitude so as to equal or overcome the sweep voltage and thuscause the trace produced by the cathode ray beam to remain motionless orto be displaced, if desired, from right to left. This method ofcontrolling the horizontal position of the trace readily permits thereproduction of the transmitted intelligence in clear and distinctcharacters of any desired configuration including scriptv Theutilization of a composite horizontal deflection voltage for characterreproduction is illustrated in graphical form and for the purpose ofexample in Figs. 2a through 2d for the production of the letter A on theface of the cathode ray tube. figuration of a portion of the horizontalsweep voltage output of the sweep generator 22. The voltage wave 28,illustrated with the amplitude thereof plotted against time, is theconventionally used saw-tooth wave form.

Fig. 2b in a similar manner graphicaly illustrates the shape of thetransmitted vertical deflection voltage 30 which, after suitableamplification in amplifier 18, is applied to the vertical deflectionplate 12. Fig. 2c illustrates the contour of the transmitted horizontaldeflection voltage 32 which, after suitable amplification in amplifier24 is introduced together with the sweep voltage 28 into the mixingnetwork 20 and the composite voltage output thereof is applied to thehorizontal deflection plate 14. Fig. 2d shows the configuration of thetrace produced by the cathode ray tube resulting from the application ofthe deflection voltages 28, 30 and 32.

For the purposes of example and to more clearly describe the operationof the device and the method of character reproduction employed therein,the formation of the letter A as illustrated in Fig. 2d from the waveforms illustrated in Figs. 2a through 20 will be described in detail.During the time interval t to application of the horizontal sweepvoltage a l: and the vertical deflection voltage a b, result in adisplacement of the trace 3}. from a to b. During the time interval tot,, appli- Fig. 2a illustrates the conall) cation of the horizontalsweep voltage b c and the vertical deflection voltage [7 c result in adisplacement of the trace 34 from b to c. After the trace 34 reachespoint 0, it is necessary to return the trace rapidly to point 0!. Toaccomplish this desired return of the trace 34 to point d, the negativepolarity horizontal sweep voltage e o; is applied to the horizontaldeflection plate 14 at time t in conjunction with the sweep voltage cand the resultant composite horizontal sweep voltage formed therebyrelocates the trace 34 at the desired location a at the desired time tor immediately thereafter. During the subsequent time interval i to 1application of the vertical deflection voltage 0 d, in conjunction witha composite horizontal deflection voltage formed by the sweep voltage cd and negative polarity horizontal deflection voltage cgi results in adisplacement of the trace 34 from d to 0. During the subsequent timeinterval 1, to 1, application of the voltages d,e,, d e and ri e,results in the displacement of the trace 34 from c to 6 thus completingthe reproduction of the desired letter A. At the time t, the removal ofthe horizontal sweep voltage e as illustrated by e g, results in a veryrapid shift of the trace 34 from c to g leaving only a faint tracetherebetween in contrast to the heavy trace utilized in the characterformation.

The point g may then serve as the commencement of a new character,spaced from the preceding character by a faint interline, which, byprior adjustment of the trace intensity may be rendered less pronounced.In general the existence of faint interlines between two characters isnot objectionable and does not detrimentally affect the clarity of thereproduced intelligence. If, however, the presence of any interliningwhatsoever is objectionable, a simple wave form is easily produced forapplication, after suitable amplification in amplifier 26, to theintensity control grid 16 to completely blank out the faint interline ortrace in the intervening space between successive letters.

The utilization of an intensity control Wave form is illustrated in Fig.2e wherein maximum intensity is maintained during the time intervalsutilized for character formation and the tube is momentarily blanked outcoincident with the application of horizontal deflection voltages c304,and esgs.

Although the above described embodiment of the receiver unit A asillustrated in the drawings utilizes, for the purposes of simplicity andexample, a single linear saw-tooth horizontal sweep voltage, it will beapparent to those skilled in this art that locally generated steppedhorizontal positioning voltages could be utilized in conjunction withhorizontal deflection voltage Wave forms representative of the algebraicsum of a saw-tooth horizontal sweep voltage and a contoured sweepcancelling voltage as illustrated in Figs. 2a and 20 for the exampleletter A. Either of these methods could be used in conjunction withsuitably shaped vertical deflection and positioning voltages, to producea plurality of lines of characters, one disposed beneath the other, onthe face of the cathode ray tube 10 instead of a single line ofcharacters described above for purposes of example. If de sired,vertical displacement of the reproduced characters could be readilyobtained by suitably phased vertical positioning voltages.

Fig. 1 also includes an embodiment, by way of example, of simplyconstructed apparatus adapted for production of the desired wave formsfor transmission purposes. There is provided a stationary cylindricaldisc 40 having a smooth surface 42 of suflicient width to support alength of previously prepared magnetic tape 44 suitably coded to providea predetermined and desired voltage wave form. The magnetic tape 44 ispreferably introduced through the aperture 46, brought out to thesurface 42 by means of the slot 48, disposed around said surface 42 asshown, and removed via said slot 48 and the aperture 50. If desired, forthe production of moving characters on the face of the cathode ray tube,means,

such as a tapepulling device 52 are provided. to advance the tape 44relative to said surface 42.

Axially mounted as at 56 on the disc is one end of a rotatable shaft 54,the other end of which is supported by a suitable supporting member suchas the bearing block 58. Mounted on theshaft 54 is a suitable pulley 60connected by a belt 62 engaging a driving pulley 6.4 driven by a motor66. Mounted on shaft 54 and rotatable therewith is a pick-up unitsupporting assembly 68 shaped to dispose a plurality of conventionallyconstructed magnetic pick-up heads 70 closely adjacent the tape 44disposed on the surface 42 of the stationary disc 40 and, in position torotatably scan said tape. The previously prepared tape 44 is magnetizedin such a way, described in detail at a later point in thisspecification, that the pick-up heads 70 have voltages generated thereinfrom which the vertical and horizontal deflection voltages and theblanking orv intensity control voltages required for control of thecathode ray can be reproduced.

In actual operation it is neither necessary nor desirable for thepick-up heads 70 to actually touch the tape 40. I have found that whenusing a modulation system and particularly the later described ratiomodulation system that satisfactory signals are obtained if the magneticpick-up heads 70 are disposed about fl inch away from ever the relativespacings may be ascertained without difliculty and is primarily anengineering or design problem.

In order to make readily available the electrical impulses. obtainedfrom the continuously rotatable pick-up heads 70, the magnetic pick-upheads 70 are electrically connected to slip rings 72. fixedly mounted onthe shaft 54 and rotatable therewith. Disposed against the surface ofthe slip rings 72 and in conducting relation therewith are a pluralityof brushes 74 individually connected to a plurality of conventionalvideo amplifiers '76 to provide an amplified output of the generatedsignals.

The output of the amplifiers 76 is then introduced into demodulatingunits 78 which are averaging circuits of the basic type described by R.R. Perron in the November 1950 issue of Electronics magazine. From thedemodulators the original wave forms which were recorded on the lengthof tape being scaned are recovered each time the scanning assemblycompletes a 360 cycle. The three sets of wave forms, i. e. vertical andhorizontal deflection voltages and the blanking or intensity controlsignal can then be transmitted on separate circuits or can be combinedand transmittedby any suitable transmission means including conventionaltelephone lines.

The receiver system described at an earlier portion of thisspecification is operable with either an externally synchronized oraccurately set free running horizontal sweep generaton It is preferredto operate with an external synchronizing signal but in the event suchsignal is obscured by noise orother interference, the device will beoperable through careful control of the repetition rate of the sweepgenerator'at the receiving station. However, in order to provide asuitable signal for the external synchronization of the cathode ray tubehorizontal sweep generator 22, the output voltage wave of which isutilized as a component of the composite horizontal deflection voltagesupplied to the horizontal deflection plates 14, a contact member 84 issuitably located on the pick-up unit supporting assembly 68 so as totrip a switch arm 36 located adjacent the slot 48 in the cylindricalface 42 of the stationary disc 40. It is clear that each time ti thepick-up heads 70 rotate past the slot 48, the contact arm'84 will tripthe switch arm 86- andthe actuation thereof may be conveniently used toactuate a pulse gen.- erator 88 the output of which provides atransmittable timed electrical impulse for synchronizing the output ofthe horizontal sweep generator 22 with the above described tape scanningsystem.

In operation of the device with the horizontal sweep generator 22 beingexternally synchronized by means of the synchronizing pulse generated byeach revolution of the rotating scanning assembly and the tape 44 beingstationary relative to the surface 42 of the disc 40, the resultantintelligence remotely reproduced on the cathode ray tube will remainstationary on the face thereof since the scanning unit permits'rotationat a sufiicient speed to cause the characters on the face of the tube toappear to be continuously present. If however the tape 44 is movedrelative to said surface 42, the scanned material will continuouslychange and the remotely reproduced characters will be displaced acrossthe face of the tube at a rate determined by the rate of tape advancerelative to said surface 42. The permitted displacement of the taperelative to the surface 42 thus results in the permitted introduction ofadditional characters on the face of the cathode ray tube coincidentwith the removal of previously scanned characters at a rate determinedentirely bythe rate of tape advance over the surface 42. The tapetherefore can be of any length and the intelligence desired to betransmitted is in no way limited by the length of tape which of coursemay be reintroduced on the surface 42 of the disc. 40 for repeattransmissions and also may be conveniently stored for future use.

As described above, the embodiment of the transmitting unit illustratedin Fig. 1 is adapted for utilization of a previously prepared magnetictape and this invention includes a simple and convenient method andapparatus for forming the transmitting tape. The essentials of the tapepreparation unit for a single character are schematically illustrated inFig. 4 and for simplicity of explanation, only the essentials of thetape preparation unit will be described, it being understood that otherand more complicated embodiments utilizing the basic principles may bereadily manufactured.

There is provided a typewriter-like unit having a key 94 adapted toactuate a type arm 96. Mounted on the end of the type arm 96is a thinmetal mask 98 having a plurality of shaped apertures 100 disposedtherein. Depression of the key 94 results in displacement of the typearm 96 moving said metal-mask 98 into and interrupting a beam of lightgenerated by a point source 102 and received through suitableslits 104in a masking element 106 disposed intermediate said point source 102 anda plurality of photocells 108. The apertures 100 in the metal mask 98are contoured in accordance with the desired voltagewave forms requiredfor the remote reproauction-of the desired character on the face of thecathode ray tube. The movement of the metal mask 98 across the-path ofthe beam of light generated by the pointsource 102 results in aprogressive interruption of said beam and a progressive variation in theamount of light received by the photocells 108 in accordance With theconfiguration of the apertures 100. The variations in the light receivedby the photocells 108 result in the generation of a voltage Wave formtherein corresponding to the desired wave shape as determined by theapertures 100 in the mask 8. Coincidently with the introduction of theapertured metal mask 98 across the beam of light, the displacement ofthe type arm 96 is also utilized to actuate a lever memher 110 tosimultaneously advance the tape so as to synchronize the rate of tapeadvance with depression of the character key 04 and the rate ofdisplacement of said mask 98 across the beam of light.

The electrical output of each of the photocells 108 is applied toaspecial ratio modulating unit to convert the photocell voltage outputinto the desired magnetization characteristic on the tape. For thepurposes of example, the ratio modulation circuit associated with one ofthe photocells 168 will be described in detail. The voltage output ofone of the photocells 108 corresponding to the intelligence desired tobe stored on the tape, is connected to the grid 116 of tube 118. Thecathode 120 thereof is connected in parallelwith the cathode 122 of thetube 124. The plates 132, of the tubes 118, 124 are connected to acommon voltage supply through plate load resistors 126 an 123respectively. The tubes 118 and 124 are arranged so that the input waveform applied to the grid 116 of tube 118 appears in magnified form atthe plate 130 of tube 124 and apears in similarly magnified but invertedform in plate 132 of tube 118. Associated with the above describedcircuits are a second pair of vacuum tubes 134 and 136 connected as aconventional symmetrical multivibrator unit having the grid resistors138 and 140 thereof connected directly to the previously describedplates 13% and 132 of tubes 124 and 118 respectively. The values of thecircuit elements forming the multivibrator must be such that therepetition frequency thereof is higher than the components of themodulating wave form in order to eifect faithful reproduction thereof.With no input wave applied to the grid of tube 118, the

plates 132 and 130 are at identical voltages and the output of thesymmetrical multivibrator provides a wave form having equal mar andspace durations. Upon application of a photocell output voltage to thegrid 116 of tube 118, the plate voltage of tube 118 decreases and theplate voltage of tube 124 increases. The variation of plate potentialsresults in an accompanying variation in the mark to space ratio in theoutput of the multivibrator although the total cycle length thereofremains unchanged. The output of the multivibrator is then preferablyapplied to conventional squaring and shaping circuits schematicallydesignated as 142, and the shaped output thereof is utilized to drive apower amplifier 144 and a demodulator 148. The output of demodulator 148is connected to grid 150a of tube 124 for the purpose of giving negativefeedback in order to improve the fidelity of the modulator system. Theoutput of the power amplifier 144 feeds current into a magnetic taperecording head 7 146 so that during the mark time interval the recorderis magnetized in one direction, while during the space interval therecorder is magnetized in the opposite direction. By the above describedmeans, the output wave form of the photocell is recorded on the magnetictape as a ratio modulated wave.

All the embodiments of the invention as described above utilize a ratiomodulated magnetic tape for control of the transmitter unit. However,other means for storing the desired wave forms, such as variations intransparency of a film or a paper tape, responsive to a photocellscanning system can also be used. Fig. 3 illustrates an alternativeembodiment utilizing a photocell scanning system that is responsive tothe variations in tape transparency. There is provided a stationaryannular ring 150 having a smooth transparent surface 152 of sufiicie-ntwidth to support a length of previously prepared light transmittabletape 154. The tape 154 is preferably introduced to the annular ring 150and surface 152 thereof by means of the diagonally disposed roller 156and removed therefrom by means of the adjacent diagonally disposedroller 15$.

Axially disposed within the ring 150 is a rotatable shaft 160 havingmounted thereon a scanning head supporting assembly 162. Mounted on theend of the scanning head supporting assembly and positioned adjacent thesurface 152 of the supporting ring 150 are a plurality of point lightsources 164. The light sources 164 are adapted to rotatably scan thetape 154 disposed on the surface 152 upon rotation of the shaft 160effected by the drive assembly including the drive motor 166, pulley168, belt and pulley 172 fixedly mounted on said shaft 160.

,lviounted on the rotatable shaft 160 and positioned thereon tocontinuously receive the light emitted by the rotating point sources 164are a plurality of photocells 174 connected to amplifying units 186which are in turn connected to the slip rings 188. Disposed intermediatethe photocells 174 and the light sources 164 and rotatable inconjunction therewith is a masking element having a plurality of slits182 included therein and positioned to limit the light received by theindividual photocells 174 to that emitted by their respective pointsources 164. In the absence of any tape disposed onthe surface 152 ofthe ring 15% light from the point sources 164 passes to the photocells174 through said slits 182 in the masking unit 130. When tape ofpredetermined varying transparency or with suitably contoured aperturesdisposed therein is mounted on the surface 152 of the supporting ring150 the wave forms represented on the tape are scanned by the slits 182in the masking unit 180 during rotation of the shaft 160 with the lightsource, slit and photocell assemblies mounted thereon. Thus rotation ofthe shaft 160 results in the production of a varying potential output ofthe photocell corresponding in shape to the contour of the wave formrecorded on the tape. The varying potential output of the photocells 174is then preferably amplified in a preamplifier unit schematically shownas 186 and presented for removal at the slip rings 188. As describedabove in conjunction with the embodiment illustrated in Fig. 1,displacement of the tape 154 relative to the surface 152 will effect acorresponding displacement of the reproduced intelligence on the face ofthe cathode ray receiver tube.

In operation of the system, the number of characters or letterspresented on the oscilloscope at any given time depends upon the numberof characters which can be represented along the length of tape scannedin one scanning cycle. This length of tape is determined by the lengthof the scanned surface, which in the described embodiment issubstantially circular, but which with other optical or mechanicalsystems could assume varied configurations.

If a seven inch diameter drum is used and one inch of tape is allowedfor each character, then 22 letters or letter spaces will appear on theoscilloscope at any given time. If the scanning system is making tenrevolutions in a second, then each letter or letter space occupies atime duration of 5 of a second in every scanning cycle. The generationof easily readable characters on the tube face under these specificoperating conditions requires a reproduction of wave form frequencycomponents up to about 1000 cycles a second for both the vertical andhorizontal deflection voltages. Using conventional methods the abovedescribed two 1000 cycle bands can be disposed for transmission as afrequency spectrum having components between about 50 and 2500 cycles asecond with an unoccupied space a few hundred cycles wide in the centerof this band. The intensity signals are placed within this space asmodulation of a 1200 cycle carrier. Spread of this carrier into thevertical and horizontal bands is unimportant as it occurs when nocharacter signals are being transmitted. Synchronizing pulses occupy thewhole band at the commencement of a'scan cycle when the band is not yetbeing used as the scanning heads have not revolved to the'point in theirscan opposite to the first letter they will read 011. V

The utilization of the horizontal sweep voltage as a component of thecomposite horizontal deflection voltage applied to the deflectionplates'14 in conjunction with the described method and apparatus forpreparation of the transmitted wave forms obviates the need of anycomplicated switching mechanisms and other constructions thatcharacterize the devices of the art and results in the reproduction ofthe transmitted intelligence in the form of characters having improvedclarity, definition and readability. Moreover the system through itspermissive simplification of structure also results in the utilizationof simple'wave forms that may readily be transmitted over conventionaltelephone lines without detrimental distortion thereof and additionallymay be readily formed and stored in a convenient manner.

In accordance with the provisions of the patent statutes, I have hereindescribed the principle of operation of this invention, together withthe elements which I now consider to constitute a workable embodimentthereof, but I desire to have it understood that the structure disclosedis only illustrative and the invention can be carried out by othermeans. Also, while it is designed to use the various features andelements in the combinations and relations described, some of these maybe altered and modified without interfering with the more generalresults outlined.

Having thus described my invention, I claim:

1. In an intelligence transmission system a transmitting unit comprisinga stationary tape supporting surface for supporting a length ofpreviously prepared tape having the intelligence desired to betransmitted incorporated thereon, means positioned to repetitively scanthe portions of said tape disposed on said supporting surface forproviding electrical signals representative of the scanned intelligenceincorporated in said tape and means responsive to said electricalsignals for generation of transmittable signals representative of thescanned intelligence.

2. The combination as set forth in claim 1 including means for effectingrelative motion between said tape and said stationary tape supportingsurface independent of said scanning means.

3. An intelligence transmission system for the visual presentation of adisplaceable continuity of transmitted intelligence on the face of acathode ray tube at a location remote from the source thereof comprisinga stationary tape supporting surface for supporting a portion of thelength of a previously prepared tape having the intelligence desired tobe transmitted incorporated therein, displaceable means positioned torepetitively scan the portions of said tape disposed on said supportingsurface for providing repeated electrical signals selectivelyrepresentative of the deflection voltages required to visually reproducethe scanned intelligence at said remotely located cathode ray tube andmeans permitting displacement of said tape relative to said supportingsurface at a rate appreciably less than the rate of displacement of thescanning means coincidently with the scanning thereof to provide ascanning means output representative of the displaceaole continuity ofscanned intelligence.

References Cited in the file of this patent UNITED STATES PATENTS1,870,989 Eldred Aug. 9, 1932 1,941,618 Nemirovsky Jan. 2, 19342,165,307 Skellett July 11, 1939 2,359,617 Bryce Oct. 3, 1944 2,369,662Deloraince et al Feb. 20, 1945 2,408,049 De Rosa Sept. 24, 19462,424,218 Begun July 22, 1947 2,429,787 Young Oct. 28, 1947 2,511,121Murphy June 13, 1950 2,539,837 Howell Jan. 30, 1951 2,552,761 Baker May14, 1951 2,556,640 Baker June 12, 1951 2,560,474 Potts July 10, 19512,561,476 Lang July 24, 1951 2,594,731 Connolly Apr. 29, 1952 2,628,539De Neergaard Feb. 17, 1953 2,656,415 Terlecki Oct. 20, 1953 2,657,377Gray Oct. 27, 1953 2,657,378 Gray Oct. 27, 1953 FOREIGN PATENTS 986,473France Aug. 1, 1951

